Assessing the Outcomes of a Long-term, Zero-emission Strategy for GoTriangle’s Transit Fleet

Abstract

The goal of this project was to assess how GoTriangle might most effectively implement battery electric vehicle (BEV) buses by analyzing possible environmental and social factors and providing recommendations for BEV bus implementation to maximize operating efficiency and social good. The core questions that drove the analyses were (1) whether GoTriangle is a good candidate for BEV bus implementation and (2) how GoTriangle might best implement BEV buses. Four analytical components were chosen to address the goals of the project based on participatory feedback from project clients: (1) analysis of potential grid impacts of charging the electric fleet, (2) comparisons between BEV bus well-to-wheel emissions and conventional diesel bus well-to-wheel emissions, (3) suitability analysis of route legs – the most granular transportation planning units used by GoTriangle, and (4) spatial analysis of emissions to address environmental health and environmental justice concerns. This report found that GoTriangle is likely a good candidate for BEV bus implementation. Increased demand to the grid would likely be negligible from a transmission point-of-view. In maximum fuel-economy scenarios with an energy mix based upon Duke Energy’s integrated resource plan, it appeared that BEV buses would contribute less emissions in every category when compared to diesel buses. Though, it should be said that comparatively larger contributions of some air pollutants were observed in minimum fuel-economy scenarios. Many bus route legs – the smallest planning units used in route optimization – appeared to be good candidates for implementation based on physical characteristics known to be associated with energy consumption. Route legs located near and around Raleigh were found to be some of the most optimal options based on their physical properties and comparatively greater potential to mitigate human exposure to criteria pollutants.